sevenspark said
That’s the “Create your Screenshots ZIP ” section of the upload instructions. It’s just a zip of your preview images (the ones you’d see when you click on the “Screenshots” button on a product page).

So, where is I must upload the HTML file?
I mean, how can I post my landing page’s file?

If you’re confused about what to put in the main download file, perhaps it would make sense to purchase a landing page so you can see what kind of files go in it. At a minimum you would have a folder for documentation and a folder for site files in the root.